Process for preparing caprolactam and polyamides therefrom

Abstract

Provided herein are processes for preparing caprolactam from a starting material such as one or more of the cis,cis-, cis,trans- and trans,trans-double-bond isomers of muconamide, muconic acid ester, or muconic acid. The starting material, intermediates, and caprolactam prepared therefrom can contain carbon atoms derived from biomass containing detectable 14 C content determined according to ASTM D6866 and optionally containing a 14 C content up to 0.0000000001% (one part per trillion). Caprolactam so prepared can be used to make various polyamides.

The invention claimed is: 
     
       1. A process for preparing caprolactam of formula 1, comprising: 
       
         
           
           
               
               
           
         
         reacting one or more of cis, cis-, cis, trans- and trans,trans-muconic acid (Q,Q-MA), directly or after converting into an intermediate product, with ammonia and hydrogen, in the presence of a catalyst; and 
         forming caprolactam therefrom. 
       
     
     
       2. The process of  claim 1 , wherein the reacting step comprises reactions via Route 1:
 converting Q,Q-MA to caprolactam in an aprotic polar solvent, using H 2  and NH 3  gases at a total initial pressure from about 250 to about 2050 psi, at a temperature from about 200 to about 300° C., and in the presence of at least one catalyst. 
 
     
     
       3. The process of  claim 2 , wherein the aprotic polar solvent is 1,4-dioxane, diglyme or DMSO. 
     
     
       4. The process of  claim 2 , wherein the aprotic polar solvent is mixed with water or an alcohol. 
     
     
       5. The process of  claim 4 , wherein the alcohol is MeOH. 
     
     
       6. The process of  claim 2 , wherein the at least one catalyst comprises one or more of Pd, Pt, Rh and Ru. 
     
     
       7. The process of  claim 6 , wherein the at least one catalyst comprises Ru and Pt or Ru and Pd. 
     
     
       8. The process of  claim 2 , wherein the at least one catalyst is present at from about 0.3 to about 1 mol %. 
     
     
       9. The process of  claim 2 , wherein the converting step takes about 0.5 to about 3 hours. 
     
     
       10. The process of  claim 1 , wherein the reacting step comprises reactions via Route 2:
 (1) converting one or both of the cis,cis-MA and cis,trans-MA to one or both of Δ α -muconolactone and Δ β -muconolactone; and 
 (2) reacting one or both of Δ α -muconolactone and Δ β -muconolactone to form caprolactam, using H 2  and NH 3  gases, and in the presence of at least one catalyst. 
 
     
     
       11. The process of  claim 10 , wherein in Route 2, step (1) the converting is conducted by heating at reflux in aq. acetic acid. 
     
     
       12. The process of  claim 11 , wherein in Route 2, step (1) the aq. acetic acid is mixed with water at a ratio of about 1:2 acetic acid:water. 
     
     
       13. The process of  claim 10 , wherein in Route 2, step (2) the H 2  and NH 3  gases are provided at a total initial pressure from about 250 to about 650 psi. 
     
     
       14. The process of  claim 10 , wherein in Route 2, step (2) the reacting is conducted at a temperature from about 200 to about 300° C. 
     
     
       15. The process of  claim 10 , wherein in Route 2, step (2) the at least one catalyst comprises one or more of Pd, Pt, Rh and Ru. 
     
     
       16. The process of  claim 15 , wherein in Route 2, step (2) the at least one catalyst comprises Ru and Pd. 
     
     
       17. The process of  claim 10 , wherein in Route 2, step (2) the at least one catalyst is present at from about 0.5 to about 5 mol %. 
     
     
       18. The process of  claim 10 , wherein Route 2, step (2) takes about 0.5 to about 3 hours. 
     
     
       19. The process of  claim 1 , wherein the reacting step comprises reactions via Route 3:
 (1) converting Q,Q-MA to one or more of cis,cis-, cis,trans- and trans,trans-muconate diester; 
 (2) converting one or more of cis,cis-, cis,trans- and trans,trans-muconate diester to one or more of cis,cis-, cis,trans- and trans,trans-muconamide (Q,Q-MCA) in aq. NH 3 ; and 
 (3) converting Q,Q-MCA to caprolactam in an aprotic polar solvent, using H 2  and NH 3  gases, and in the presence of a catalyst. 
 
     
     
       20. The process of  claim 19 , wherein in Route 3, step (1) the converting is conducted in aq. NaOH with dimethylsulfate. 
     
     
       21. The process of  claim 20 , wherein in Route 3, step (1) the converting is conducted at room temperature. 
     
     
       22. The process of  claim 19 , wherein Route 3, step (1) includes converting trans,trans-MA to trans,trans-muconic diester in methanol containing a catalytic amount of sulfuric acid while heating at reflux. 
     
     
       23. The process of  claim 19 , wherein in Route 3, step (2), the aq. NH 3  is mixed with an alcohol. 
     
     
       24. The process of  claim 23 , wherein the alcohol is MeOH or EtOH. 
     
     
       25. The process of  claim 23 , wherein a ratio of the aq. NH 3  to the alcohol is about 1:1. 
     
     
       26. The process of  claim 19 , wherein in Route 3, step (3) the aprotic polar solvent is THF, 1,4-dioxane or diglyme. 
     
     
       27. The process of  claim 19 , wherein in Route 3, step (3) the H 2  and NH 3  gases are provided at a total initial pressure from about 1000 to about 1600 psi. 
     
     
       28. The process of  claim 19 , wherein in Route 3, step (3) the converting is conducted at a temperature from about 200 to about 300° C. 
     
     
       29. The process of  claim 19 , wherein in Route 3, step (3) the catalyst comprises 2CuO—Cr 2 O 3  or Pd. 
     
     
       30. The process of  claim 19 , wherein in Route 3, step (3) the catalyst is present at from about 5 to about 50 mol %. 
     
     
       31. The process of  claim 19 , wherein Route 3, step (3) takes about 1 to about 3 hours. 
     
     
       32. The process of  claim 19 , wherein the muconic diester is dimethyl muconate. 
     
     
       33. The process of  claim 1 , wherein the reacting step comprises reactions via Route 4:
 (1) converting Q,Q-MA to one or more of cis,cis-, cis,trans- and trans,trans-muconate diester; 
 (2) converting one or more of cis,cis-, cis,trans- and trans,trans-muconate diester to one or more of cis,cis-, cis,trans- and trans,trans-muconamide (Q,Q-MCA) in aq. NH 3 ; 
 (3) reducing the Q,Q-MCA to adipamide using H 2 , in the presence of a first catalyst; and 
 (4) reducing the adipamide to yield caprolactam in an aprotic polar solvent, using H 2  and NH 3  gases, in the presence of a second catalyst. 
 
     
     
       34. The process of  claim 33 , wherein in Route 4, step (1) the converting is conducted in aq. NaOH with dimethylsulfate. 
     
     
       35. The process of  claim 34 , wherein in Route 4, step (1) the converting is conducted at room temperature. 
     
     
       36. The process of  claim 33 , wherein Route 4, step (1) includes converting trans,trans-MA to trans,trans-muconate diester in methanol containing a catalytic amount of sulfuric acid while heating at reflux. 
     
     
       37. The process of  claim 33 , wherein in Route 4, step (2), the aq. NH 3  is mixed with an alcohol. 
     
     
       38. The process of  claim 37 , wherein the alcohol is MeOH or EtOH. 
     
     
       39. The process of  claim 37 , wherein a ratio of the aq. NH 3  to the alcohol is about 1:1. 
     
     
       40. The process of  claim 33 , wherein in Route 4, step (3) the H 2  is provided at an initial pressure from about 300 to about 1600 psi. 
     
     
       41. The process of  claim 33 , wherein in Route 4, step (3) the first catalyst comprises 2CuO—Cr 2 O 3 , Pd, Pt, Rh or Ru. 
     
     
       42. The process of  claim 33 , wherein in Route 4, step (3) the first catalyst is present from about 5 to about 25 mol %. 
     
     
       43. The process of  claim 33 , wherein in Route 4, step (3) the reducing is conducted at a temperature from about 200 to about 300° C. 
     
     
       44. The process of  claim 33 , wherein in Route 4, step (4) the aprotic polar solvent is diglyme. 
     
     
       45. The process of  claim 33 , wherein in Route 4, step (4) the H 2  and NH 3  gases are provided at a total initial pressure from about 500 to about 1650 psi. 
     
     
       46. The process of  claim 33 , wherein in Route 4, step (4) the second catalyst comprises one or more of Pd, Pt, Rh and Ru. 
     
     
       47. The process of  claim 33 , wherein in Route 4, step (4) the second catalyst is present from about 5 to about 10 mol %. 
     
     
       48. The process of  claim 33 , wherein in Route 4, step (4) the reducing is conducted at a temperature from about 200 to about 300° C. 
     
     
       49. The process of  claim 33 , wherein in Route 4, step (4) takes about 1 to about 3 hours. 
     
     
       50. The process of  claim 33 , wherein the muconic diester is dimethyl muconate. 
     
     
       51. A process for preparing nylon 6, comprising: polymerizing caprolactam, wherein the caprolactam is prepared according to the process of  claim 1  from biomass-derived Q,Q-MA and contains a detectable amount of  14 C determined according to ASTM D6866. 
     
     
       52. The process of  claim 51 , wherein the caprolactam contains up to 0.0000000001%  14 C. 
     
     
       53. A process for preparing a polyamide, comprising: reacting caprolactam with a compound having at least two amide-forming groups, wherein the caprolactam is prepared according to the process of  claim 1  from biomass-derived Q,Q-MA and contains a detectable amount of  14 C determined according to ASTM D6866. 
     
     
       54. The process of  claim 53 , wherein the caprolactam contains up to 0.0000000001%  14 C. 
     
     
       55. The process of  claim 53 , wherein the compound having at least two amide-forming groups comprises one or more of aliphatic or aromatic amino carboxylic acids, aliphatic or aromatic diamines, aliphatic or aromatic dicarboxylic acids, or salts or halides or esters thereof. 
     
     
       56. The process of  claim 1 , wherein the reacting step reactions via Route 5: converting Q,Q-MA to adipic acid, and reacting the adipic acid with the ammonia and hydrogen in the presence of at least one catalyst to form caprolactam. 
     
     
       57. The process of  claim 56 , wherein the at least one catalyst comprises Ru. 
     
     
       58. The process of  claim 53 , further comprising: converting the Q,Q-MA to adipic acid; reacting adipic acid with ammonia and hydrogen in the presence of a catalyst; and forming caprolactam therefrom.